Slack-adjuster.



FRANCIS DEWEY Evnan'i'r, or sumac LAKE, new form.

' sLacx-anJUsi'ER.

specification of Letters IPatent. I

3 Application filed Jul 31,1 11. serial n isam.

To all whom it may concern.

. 'Be it known that I, FRANCIS DEWEY EVERETT, a citizen of the United States, residing at Saranac Lake, in the county of Es- I sex and State of New York, have invented a, certain new and useful Improvement in Slack-Adjusters, of which the following-is a specification, reference being hadtherein to the accompanying drawings. v 'My 'nvention relates to a slack ad uster mechanism for taking up thewear between two friction'surfaces, such as brakes on an automobile or a friction driving mecha-. msm' where, when the tenslon 1s released in connection with 'other classes of appa-- ratus or mechanism.

v 80 "The' invention will be, fully understoodthere must always be the same amount ofclearance, and where the movement of the. operating device is limited,-a's in the case of the brake pedal of an automobile.

The inventionis an improvement on the device shown and described in an application filed by me April 11,- 1917, Serial No.

161,310,, allowed June 22nd, 1917.

The'invention as shown in the drawings,- and 1 as described herein isembodied 1na slack adjuster applied to brakes of an automobile, but it will be understood that the invention is adapted for application to and use from .the following description, taken in connection with the accompanying draw- Kings, and the novel features thereof are pointed out and clearly defined in the claims at the end of the specification. 1

In the drawings, Figure 1 1s a longitudi nal section of an automobile chassis or frame with my slack adjuster mechanism combined therewith.

Fig. 2 is a longitudinal section on anen:

larged scale showing the slack adjuster mechanism detached and some of the connectingparts partly broken away.

Fig. 3 isa section on line 3-3 of Fig. 2."

Fig, 4- is a longitudinal sectional view showing a modified form of mechanism embodying the invention, detached. A

Fig. 5 'is a plan view of the modified form shown .in Fig. 4.

Referring now to the drawings, 1 is the frame, of an automobile whichm'a'y. be of anyjordina'ry construction; 2 and 3 are re-.-. 'spectively the frontandrear axles, and 4 and "5 are respectively, the front andgrear wheels. 6 isthe foot pedaland 7 th'e'connesting rod which connects the brake pedal,

6 withthe lever 8 on the cross rod9 connected with the frame. The cross rod 9 is connected through [rods or connections 10 with the angle levers 11 which are connected with the brake band 12 in the usual and-well known'way. Only one of said rods Pa tented Aug. 191 s. I

10 and .levers 11 is shown 1 in the drawings.

A spring 13 acts torelease the brake when the foot pedalis released, and a spring 40 serves to return the foot pedal 6 to its nor-. mal position when it is released.

The intermediate mechanism connecting the connecting rod 7 with the foot pedal 6 may be of' the same general character as shown and described in said previous appli cation and which is herein shown and de- 'scrlbedmerely forthe purpose of clearly. 'understanding the present invention.

' A box or casing 14 has two forwardly ex tending arms 15 (only one of which is shown in the drawings) between which extends the foot brake pedal 6. Thesaid pedal is pivotally connected with said arms 15.

' The connectin rod 7 has an enlarged end 71 preferablyv 0 square shape in cross section which is locatedin the lower part of the box or casing 14 and movesin a lengthwise direction, one end of. the box having an opening. for the enlarged portion 71 to slide "through, and the other end of the box'having a-smaller opening-for the rod 7. Within 'the box liare located a'series of separate plates or washers '16 each of which has a [forked lower end, the/spaces between the shoulder-formed by the enlarged head 71 of the rod and the-adjacent end of the box,

as shown inFig. 2, if the movement is,

enough to afford suflicient space, one or moreof the plates 16 will'be released and drop down on to the smaller portion of the rod" 7, as shown in Fig. 2, the number of plates which drop down being according to the space, thus preventing, the rodffrom'being moved back againwith relation to the box,

,a'nd-the shoulder on the enlarged head of the rod will be engaged by one of said washers on plates instead of-by the'rear end of the box.

ame.

' A second box or casing which is nade fast to the r a 19 is rovided,

aid box may be formed with a flange 41 having bolt washers being formed with slots 37 of sufii;

cient height so that when the slide rod or Y bar 20 is moved forward, that is, toward the right as viewed in Fig. 2, one or more of the washers 21, as the case may be according to the distance that the slide bar is moved forward, may drop down behind the rear end of said slide bar to form a stop to prevent the return of the slide bar to the left.

A spring 35 which is secured to the box 19 bears against the said slide bar 20 and acts as'a sort of brake or check to prevent longitudinal movement of the slide bar 20, due to vibration or any similar slight. cause, but does not prevent the movement of the bar when acted upon positively. The forward end ofthe slide bar 20 is bent down and forked or slotted, thereby forming a slot or opening 44 through which asses the rod 7 Mounted fast to the rod are two stops 30 and 31, oneon either side of the downwardly projecting end of the slide bar 20, said stops being spaced apart from each other a suflicient distance so that there is a clearance'spacet'suflicient to allow for the normal movement of the connecting rod without moving the slide bar that is, at the end of the forward stroke of the connecting rod, when the pedal is depressed to set the brake, the stop 30 will be in engagement with the rear face of the downwardly extending end of the slide bar, and at the end of therearward or returning movement of the connecting rod when the brake is released, the stop 31 will engage the front face of the downwardly extending 'end of the slide bar. I

The stops are so spaced apart and adjusted on the connecting rod that'in the normal movement of the connecting rod in setting the brakes and releasing them, the said stops-will merely come into contact with-said slide bar, without moving it.

When, however, the wear on the brake surfaces requires a longer movement of the rod 7 to set the brake, this will cause the rod 7 to move. to the right as viewed in'Fig. .2 enough more than the normal length of the stroke to make up for the wear, and as the stop'3 0 will engage the slide'bar when the connecting rod is moved its normal distance, any continued movement beyond the normal distance, will cause the stop to move the slide bar to the right aedistance equal,

to the excess or additional movement ofthe connecting rod. If this additional move- -ried forward and thereby cause the rod? to move forward. The movemal position, but the connectin rod 7 will be moved back as much short 0 its original normal position as the thickness of the plate 21'. which has dropped down in behind the.

slide bar 20. This will leave a corresponding space between the shoulder at the real. end of the enlarged portion or head 71 and:

the rear wall of the box 14 equal in length to the space which has been filled by the dropping of the plateor plates 21 in the box 19. This will allow one or more plates 16 in the box 14 to drop down on to therod 7 behind the shoulder of the enlarged head 71 so that when the pedal is again depressed to apply the brake, the box 14 will be carimmediately ment now will at first be the regular normal length of stroke but under continued wear, it will gradually be slightly increased, until the slack is suflicient'for the amount to be taken up by another-one of the washers.

In the modification shown in Figs. 4 and 5, instead of having two stops fixedly mounted on the rod '7 a. certain distance apart from each other, and forming the slide bar with a downwardl extending arm, having a slot through w ich the connecting rod loosely passes, there is provided a single stop 46 rigidly secured to the connecting rod 7 as by a screw 47 and forming the slide bar 48 with an elongated slot 49 which is engaged by a finger 50 projecting from the stop 46. The said slot 49 is of just theright length so that as the connecting .rod moves in its normal length of stroke, it will alter-' 'plate will drop down behind the rear end of the slide bar and the slack will be taken up as already described.

Thusthe normal length of stroke of the connecting rod in setting or releasing the brakes in the first form of'device described will be regulated by the distance between the stops .30 and 31, and in the inodified form of device as shown in Figs. 4 and 5, the distance willjbe regulated by the length of the slot 49. The method of action is the same in both cases.

What. I claim is: 1.- A slack adjuster to automatically take upthe wear between two friction surfaces,

comprising a reciprocatable member or rod connected withone of said friction surfaces,

means for reciprocating said rod to move the friction surface connected therewith toward and from the other friction surface, a sta tionary box or casing, a member which is slidable within said box or casinlgI1 a loose 15 one of which engaging surfaces moves said slide member in an outward direction from the casing whenever sald 'connectmg rod moves on its forward stroke more than 1ts normal distance, and a series of separate plates or washers within said casing which are normally supported upon said slide member and which are severally adapted to dropv down behind the end of said slide member' whenever said slide member is moved out from under any one or more of said plates or washers, and thereby to limit the return movement of said slide meinber. v

2. A slack adjuster to automatically take upthe wear between two friction surfaces,

comprising a reciprocatable rod, connected with one of said friction surfaces,means for reciprocating said rod to move the friction surface connected therewith toward and from the other friction surface, astationary box orcas'ing, a memberwhich is slidable 'within said box or casing, a loose connection between said slidable member and said reciprocatable rod whereby said rod is permitted a predetermined range of movement with relation to said slidable member, means connected with said rod having portions which alternately engage difierent portions of said slidable member at the opposite ends of the normal stroke of said rod, one of which engaging surfaces moves said slidable member in the box in an outer direction whenever said rod moves on its I forward stroke more than its normal distance, a series of separate plates or washers, within said box or casing which are normally supported upon, said slidable member. in said casing and which are severally adapted to drop down behind the end of sa1d, slidablemember whenever sa d slidable member is moved out from under any one or more of said plates 01" washers, and thereby to limit the return movement of said slldable member therein, and a spring brake which en'- gages the said slidable member to prevent accidental silding movement thereof.

3. A slack adjuster to automatically take up the wear between two friction surfaces .in which one of the friction surfaces is movable toward and from the other, and i provided with a connecting rod and mechanism for actuating said rod to move the friction surface connected therewith toward and from the other friction surface, said slack ad uster comprising a stationary device, a

slide member connected with the stationary device, a loose connection between said slide member and said connecting rod whereby said connecting rod is permitted. a predetermined range of movement with relation to said slide member, means connected with said rod having" faces which are respectively adapted to be brought into'contact with said slide member at the opposite ends of the normal stroke 'of said connecting rod without actuating said slide member, the surfaceon said connecting rod which engages said slidemember on the stroke which applies the brake, actuating said slide member in an outward direction with relation to said fixed member whenever the said friction applying stroke of the connecting rod exceeds its normal length, and stop mechanism controlled by said slide member in such mannerthat when saidslide member is moved outward with relation to said fixed member, said stop mechanism will automatically move to a position which prevents a return movement of said slidemember in relation to said fixed member; I

4. A slack adjuster to automatically take up the wear between two friction surfaces, in which one of the friction surfaces is movble toward and from the other, and is proided with-a connecting rod and mechanism a for actuating said rod to move the friction surface connected therewith toward andfrom the other friction surface, said slack adjuster comprising a stationary device, a

slide member connected with the stationary device, a loose connecticn between said slide member and said 'con-nectmg rod whereby said connecting rOd is'permitted a predetermined range of' movement with relation to said slide member,'engag1ng means connected with said rod which respectively are' barely brought into engagement with said slide member at the opposite ends of the n'ormalstroke of said connecting rod, the

surface on'said'. connecting rod which engages said slide member on the stroke which applies the brake, causing said'slide'member toibe moved with relation to said fixed mem ber whenever the. said friction applying stroke of the connecting rod exceeds its normil length, stop mechanism controlled by said slide member in such manner that when said sllde member is moved outward with relation to said fixed member, said stop mechanism will automatically move to a position which prevents a, return movement of said slide member in relation to said fixed & member, and a spring friction or retarding member connected with said fixed 'member which engages said slide member to prevent accidental movement of the slide member with relation to the fixed member, but which yields to the positive actuation of the en- 1 gaging member of the connecting rod.

In testimony whereofI aflix my signature.

FQDEWEY EVERETT. 

